According to GM, about 95,000 faulty switches were sold to dealers and aftermarket wholesalers. Of those, about 90,000 were used to repair older vehicles that were repaired before they were recalled in February.

GM said because “it is not feasible to track down all the parts, the company is taking the extraordinary step” to recall all model years of its Chevrolet Cobalt, HHR, Pontiac G5, Solstice and Saturn Ion and Sky models.

“We are taking no chances with safety,” said GM CEO Mary Barra, in a statement. “Trying to locate several thousand switches in a population of 2.2 million vehicles and distributed to thousands of retailers isn’t practical. Out of an abundance of caution, we are recalling the rest of the model years."

As with the earlier recalls, if the torque performance is not to GM specification, the ignition switch may unintentionally move from the “run” position to the “accessory” or “off” positions, leading to a loss of power. The risk may be increased if the key ring is carrying added weight or if the vehicle goes off road or experiences some jarring event, including rough roads. If the key turns to one of those positions, officials say the front air bags may not work if there's a crash.

The problem has been linked to 31 front-end crashes that caused 12 deaths.

GM currently faces NHTSA, two congressional committees and the Justice Department investigating its actions in recalling the older-model vehicles for faulty ignition switches. The automaker, according to reports, knew that the switches could unexpectedly shut down car engines and cause drivers to lose control since the early-2000s. But the vehicles were not recalled until last month.

To fix the problem, dealers will replace the ignition switch to prevent the unintentional or inadvertent key movement. Until this correction is performed, GM says it is very important that drivers remove all items from their key rings except for the ignition key.

GM said vehicle owners affected by the expanded recall will be notified by mail the week of April 21 -- about two weeks after dealers are expected to start receiving parts for the first round of recalled vehicles.

“We are going to provide our customers with the peace of mind they deserve and expect by getting the new switches into all the vehicles,” Barra said.

The initial ignition switch recall on Feb. 13 covered about 780,000 Chevrolet Cobalts and Pontiac G5s and was widened less than two weeks later by more than 800,000 additional vehicles.

Some industry analysts have praised Barra for her efforts regarding the ignition switch recall. In addition to a number of recent videos to consumers, Barra also named a new executive to oversee vehicle safety; listened into complaints at a GM call center; and kept employees up-to-date on how GM plans to fix the problem, among other things.

Even with the recall now at about 2.6 million vehicles, some analysts continue to see GM's handling of the situation as a positive.

“This move continues the proactive stance Mary Barra and GM have displayed since the recall first broke in February," said Kelley Blue Book senior analyst Karl Brauer. "It seems highly unlikely these later models would be impacted by the faulty ignition switch plunger, but it’s possible, and GM appears focused on removing any chance of this problem occurring in the future."